1、Designation:D5970/D5970M16(Reapproved 2021)Standard Test Method forDeterioration of Geotextiles from Outdoor Exposure1This standard is issued under the fixed designation D5970/D5970M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,th
2、e year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers evaluating the deterioration intensile strength and strain after outdoor exposure.1.2 The
3、 deterioration is assessed as a reduction in strengthand strain at failure from the unexposed geotextile.1.3 The specific location of the light and weather exposureis made on the basis of a site-specific decision between theparties involved.1.4 The values stated in either SI units or inch-pound unit
4、sare to be regarded separately as standard.The values stated ineach system are not necessarily exact equivalents;therefore,toensure conformance with the standard,each system shall beused independently of the other,and values from the twosystems shall not be combined.1.5 This standard does not purpor
5、t to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 This international standard was d
6、eveloped in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Docu
7、ments2.1 ASTM Standards:2D4439 Terminology for GeosyntheticsD5035 Test Method for Breaking Force and Elongation ofTextile Fabrics(Strip Method)G7/G7M Practice for Atmospheric Environmental ExposureTesting of Nonmetallic MaterialsG113 Terminology Relating to Natural and Artificial Weath-ering Tests o
8、f Nonmetallic Materials3.Terminology3.1 For definitions of terms related to geosynthetics,refer toTerminology D4439.3.2 For definitions of terms related to weathering,refer toTerminology G113.3.3 Definitions:3.3.1 ultraviolet degradationthe photochemical changeinduced by exposure to ultraviolet radi
9、ation that results indeterioration of the performance characteristics of the poly-meric structure.3.3.2 weathering degradationthe change induced by ex-posure to outdoor conditions that results in deterioration of theperformance characteristics of the polymeric structure.4.Summary of Test Method4.1 G
10、eotextile coupons are attached to a test frame oriented45 from the horizontal and facing the equator at a designatedlocation for exposure times of 1,2,4,8,12,and 18 months.Exposure shall begin so as to ensure that material is exposedduring the maximum intensity of ultraviolet light of the year.Unles
11、s otherwise specified,the test should be initiated in Mayin the northern hemisphere,and in November in the southernhemisphere.4.1.1 Unexposed coupons,or file specimens according toTerminology G113,shall be retained for testing.4.2 After each exposure time,the appropriate coupons arebrought into a la
12、boratory for strength determination.Theresults of these tests are compared to the strength determinedfor the unexposed coupons.The user may be interested inexposure times other than specified in this test method.Thesetimes should be noted in reporting the results.4.3 The results are presented in the
13、 form of various plots.4.4 Additional recommendations may be found in PracticeG7/G7M and Terminology G113.5.Significance and Use5.1 Outdoor exposure tests at one location may not beapplicable to a project site at another location.This test method1This test method is under the jurisdiction of ASTM Co
14、mmittee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.02 on Endur-ance Properties.Current edition approved May 1,2021.Published May 2021.Originallyapproved in 1996.Last previous edition approved in 2016 as D5970/D5970M 16.DOI:10.1520/D5970_D5970M-16R21.2For referenced ASTM
15、 standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19
16、428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1evaluates geotextiles under site-specific atmospheric condi-tions over an 18-month period.A degradation curve as per10.8,based on strength,elongation,or modulus,or
